SARS-CoV-2 infection – spread and pathogenicity
More details
Hide details
Department of Preclinical Conservative Dentistry and Preclinical Endodontics, University of Medical Sciences, Poznań, Poland
Anna Szkaradkiewicz-Karpińska   

Department of Preclinical Conservative Dentistry and Preclinical Endodontics, University of Medical Sciences, Poznań, Poland
J Pre Clin Clin Res. 2020;14(2):49–51
In December 2019, a new disease, similar to severe acute respiratory syndrome (SARS), was reported in Wuhan, China. It was quickly indicated that the causative agent of this new coronavirus disease 2019 (COVID-19) is a previously unknown coronavirus, now called SARS coronavirus 2 (SARS-CoV-2). The result of the global outbreak of COVID-19 in the world (currently COVID-19 is present on all continents, except Antarctica) is the pandemic status 2019–2020, as declared by the WHO and Public Health Emergency of International Concern (PHEIC).The virus has a high epidemic potential and is effectively transmitted between humans. The primary route for SARS-CoV-2 infection to spread is air-droplet transmission. In addition, SARS-CoV-2 can be transmitted through direct contact with an infected person, or indirectly via coronavirus-contaminated materials or objects. Current data also indicate the possibility of an alternative route of SARS-CoV-2 infection – through the gastrointestinal tract. The article discusses various SARS-CoV-2 transmission options, with particular attention paid to the role of saliva and gastrointestinal tract in the spreading of the virus. Current data on SARS-CoV-2 pathogenicity and clinical symptoms of COVID-19 are also analyzed. Expanding knowledge about SARS-CoV-2 infection, especially in terms of its spread, will contribute to further actions aimed at preventing transmission of this pathogen.
World Health Organization. Pneumonia of unknown cause – China. 2020
World Health Organization. Novel coronavirus – China. 2020.
3. (accessed on 21 April 2020).
Lu R, Zhao X, Li J, Niu P, Yang B, Wu H, et al. Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet. 2020; 395(10224): 565–574.
Chan JF, Yuan S, Kok KH, To KK, Chu H, Yang J, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet. 2020; 395(10223): 514–523.
Centers for Disease Control and Prevention. 2019 Novel coronavirus, Wuhan, China: 2019-nCoV situation summary. Appendices January 28, 2020
Centers for Disease Control and Prevention. Infection control. 2019 Novel coronavirus, Wuhan, China. 2020
Szkaradkiewicz A. Novel human coronaviruses – SARS-CoV, MERS-CoV and 2019-nCoV (COVID-19). Zakażenia XXI wieku. 2020; 3(1): 1–6.
To KK, Tsang OT, Chik-Yan Yip C, Chan KH, Wu TC, Chan JMC, et al. Consistent detection of 2019 novel coronavirus in saliva. Clin Infect Dis. 2020; doi: 10.1093/cid/ciaa149.
Liu L, Wei Q, Alvarez X, Wang H, Du Y, Zhu H, et al. Epithelial cells lining salivary gland ducts are early target cells of severe acute respiratory syndrome coronavirus infection in the upper respiratorytracts of rhesus macaques. J Virol. 2011; 85(8): 4025–4030.
Spagnuolo G De Vito D, Rengo S, Tatullo M. COVID-19 Outbreak: an overview on dentistry. Int J Environ Res Public Health. 2020; 17(6). doi: 10.3390/ijerph17062094.
van Doremalen N, Bushmaker T, Morris DH, Holbrook MG, Gamble A, Williamson BN, et al. Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1. N Engl J Med. 2020 doi: 10.1056/NEJMc2004973.
Zhang H, Kang Z, Gong H, Xu D, Wang J, Li Z, et al. The digestive system is a potential route of 2019-nCov infection: a bioinformatics analysis based on single-cell transcriptomes. bioRxiv. doi:
Gu J, Han B, Wang J. COVID-19: Gastrointestinal Manifestations and Potential Fecal-Oral Transmission. Gastroenterology. 2020. doi: 10.1053/j.gastro.2020.02.054.
Holshue ML, DeBolt C, Lindquist S, Lofy KH, Wiesman J, Bruce H, et al. First case of 2019 novel coronavirus in the United States. N Engl J Med. 2020; 382(10): 929–936.
Zou X, Chen K, Zou J, Han P, Hao J, Han Z. Single-cell RNA-seq data analysis on the receptor ACE2 expression reveals the potential risk of different human organs vulnerable to 2019-nCoV infection. Front Med. 2020. doi: 10.1007/s11684-020-0754-0.
Hoffmann M, Kleine-Weber H, Schroeder S, Krüger N, Herrler T, Erichsen S, et al. SARS-CoV-2 cell entry depends on ACE2 and TMPRSS2 and is blocked by a clinically proven protease inhibitor. Cell. 2020.
Xu H, Zhong L, Deng J, Peng J, Dan H, Zeng X, et al. High expression of ACE2 receptor of 2019-nCoV on the epithelial cells of oral mucosa. Int J Oral Sci. 2020; 12, 8.
Chai XQ, Hu LF, Zhang Y, Han W, Lu W, Ke A. Specific ACE2 expression in cholangiocytes may cause liver damage after 2019-nCoV infection. bioRxiv.
Sims AC, Baric RS, Yount B, Burkett SE, Collins PL, Pickles RJ. Severe acute respiratory syndrome coronavirus infection of human ciliated airway epithelia: role of ciliated cells in viral spread in the conducting airways of the lungs. J Virol. 2005; 79(24): 15511–15524.
Huang Ch, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. 2020; 395: 497–506.
Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA. 2020. doi: 10.1001/jama.2020.1585.
Wan SX, Yi RJ, Fan SB, Lv JL, Zhang XX, Guo L, et al. Characteristics of lymphocyte subsets and cytokines in peripheral blood of 123 hospitalized patients with 2019 novel coronavirus pneumonia (NCP). medRxiv. /
Lin L, Lu L, Cao W, Li T. Hypothesis for potential pathogenesis of SARS-CoV-2 infection-a review of immune changes in patients with viral pneumonia. Emerg Microbes Infect. 2020; 9(1): 727–732.
Wu Z, McGoogan JM. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China summary of a report of 72314 cases from the Chinese Center for Disease Control and Prevention. JAMA. 2020; 323(13): 1239–1242.
Cao Y, Liu X, Xiong L, Cai K. Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2: A systematic review and meta-analysis. J Med Virol. 2020. doi: 10.1002/jmv.25822.
Heydari K, Rismantab S, Shamshirian A, Lotfi P, Shadmehri N, Houshmand P. Clinical and paraclinical characteristics of COVID-19 patients: A systematic review and meta-analysis. medRxiv.
Qiu H, Wu J, Hong L, Luo Y, Song Q, Chen D. Clinical and epidemiological features of 36 children with coronavirus disease 2019 (COVID-19) in Zhejiang, China: an observational cohort study. Lancet Infect Dis. 2020; S1473-3099(20)30198-5.
Tao Y, Cheng P, Chen W, Wan P, Chen Y, Yuan G. High incidence of asymptomatic SARS-CoV-2 infection, Chongqing, China. medRxiv; 2020. doi: 10.1101/2020.03.16.20037259.